In all of this, libraries and universities do not always know what's going to be useful and essential to scholarship in the future. One of the most regrettable decisions in the Bodleian Library's history was to sell its copy of the First Folio, deposited by the printer on its publication in 1623 in accordance with an agreement with the Stationers' Company. When the Third Folio reached the library in about 1664, it seems that the Bodleian decided the First Folio was superfluous and sold it with other items for £24. At the turn of the 20th century, the library bought it back from a private owner for the then huge sum of £3,000. Predicting what will be of value and importance in the future is particularly difficult and it is easy to get this badly wrong. Who would have thought that such ephemeral items as broadside ballads, almanacs, popular pamphlets, comics, shop and manufacturers' catalogues, pulp fiction or science fiction were worth preserving or would one day become the objects of serious study? 

The same goes for buying new, contemporary material. Libraries, especially in the US, have long sought to build relationships with authors to acquire material while they are still writing. Much slightly older material has already found a good home elsewhere and there is little point in thinking that even a couple of poetical manuscripts, a handful of letters and a few first editions will bring scholars from around the world to work in a research library. They want the sort of breadth and depth that the Harry Ransom Center at the University of Texas at Austin or Emory University's Manuscript, Archives, and Rare Book Library, or the Brotherton Library at Leeds University, or the Bodleian and British Libraries themselves have to offer. Building a new collection in any area, but especially in modern literature, is a difficult business and requires, knowledge and taste, a good deal of research, and close links with academics and those in the antiquarian trade who tend to know a lot about the field and the market. Private collectors often sell books to buy other books; enthusiasms and interests change; several less-loved volumes may be sacrificed to acquire the most desired item; a less interesting or damaged copy may be traded in to acquire a better one. These are private transactions and personal matters that satisfy an individual's whims. Institutional libraries have a heavier responsibility and cannot and should not act in such ways.

Although the fact that books printed before 1800 (and many thereafter) are not duplicates is well established, still comes the cry from librarians and those who should know better that digital images are adequate replacements for the originals or sufficient for most purposes. We have been here before with microfilms and microfiches and the limitations of such surrogates are still the same. They are only as good as the people or companies that make them: they may miss pages out, photograph them in the wrong order, trim margins containing all-important material, doctor images in one way or another, and even reproduce the wrong book. Moreover in the case of printed books, only one copy of the book tends to be reproduced: it is good to have the singularity of that copy recognised, but what of all the rest? Most digital images fail to do justice to specific details of binding, ownership and annotation. They cannot, except in rare cases, give any indication of the nature of the paper on which the book has been printed. Anyone who has worked extensively with a digital- image book will be all too aware of the limitations of the technology. Digital images of books are extraordinarily useful and can save a great deal of time, but they are not intended to and can never be substitutes for the original. They complement but can never replace direct firsthand examination of actual copies.

The sale of the Sterling Folios failed because people who care about Shakespeare, old books more generally, libraries and universities and more specifically Senate House and the University of London, mounted a swift and powerful campaign against the proposal. They used social media and the extraordinary power of the internet to point out the unsatisfactory and unconsidered way in which the University Library and its trustees had gone about realising what was supposed to be no more than a proposal. There are lessons to be learnt here both for those who are thinking about selling books from institutional libraries in the future and for those who seek to oppose such sales.